Value of the magnetic resonance imaging in patients with painful lumbar spinal stenosis (LSS) undergoing lumbar epidural steroid injections.

Objectives: Purpose of this study is to examine the relationship between the magnetic resonance imaging (MRI) findings, pain scores, and opiates use in patients with lumbar spinal stenosis (LSS) undergoing lumbar epidural steroid (LES) injections by retrospective review of 719 patients' electronic medical records.

Methods: Reviewed were Visual Analog Scale (VAS) pain scores and opioid use before and 8 to 12 weeks after series of LES injections. The stenosis pain index (SPI) was produced by adding an assigned numerical value of severity (1=mild, 2=moderate, 3=severe) to the number of lumbar vertebral levels affected by LSS on MRI (lateral or central).